I didn't have to send email; all I did was type that url into the time server block in Date and Time preferences.
I ran a time app in Linux somewhere around eight years ago. I read up on NTP *at the time* and came to the conclusion that they liked to be
notified that their server was being accessed by some random user. At least, the ones closest to me did. Times have changed. Or perhaps I
misread or misremember. I guess it's moot now. Certainly with a Mac user using Apples NTP server, anyhow.
Yep, just a few years back I notified a couple of University servers that
I
was going to use their stratum 2 servers. Ever since OpenBSD wrote their
own ntpd server I've been using their default ntpd.conf which syncs with pool.ntp.org: